1. Field of the Invention
The present invention relates generally to a diver's snorkel and more particularly to a uniquely configured snorkel mouthpiece section which is designed to minimize the collection of water in the mouthpiece.
2. Background Art
A snorkel diver may encounter rough surface conditions such as splashing, waves or surface wind chop. As a result, water in the form of droplets will enter the open top of the snorkel tube or conduit and make their way down the walls of the tube or conduit toward the mouthpiece at the lower end. The resulting accumulation of sea water in the mouthpiece requires the diver to either purge the snorkel or remove the mouthpiece and turn it into an inverted position so that the accumulated water can drain out. Frequent purging or removal of the mouthpiece can be an annoying and inconvenient distraction which can substantially reduce the enjoyment of snorkel diving.
Therefore, there have been frequent prior art attempts to construct a snorkel so that water droplets do not enter the mouthpiece. By way of example:
U.S. Pat. No. 4,884,564 to Lamont is directed to a mechanism for more efficient purging of the water column and more efficient water drainage to enhance snorkel breathing. This snorkel patent utilizes one or more of the following features: a trough in the partition between the breathing tube and the purge conduit using a hole to drain water and prevent back flow; a deflector on the mouthpiece side of the partition to resist water flow towards the mouthpiece and promote drainage through a hole in the partition; a Venturi-type construction in the breathing tube to increase water pure in efficiency for a given exhalation effort; as well as decrease resistance to the air flow to the user; and an air trap immediately exterior to the purge valve and the branch conduit for reducing the resistance to opening of the valve and thus promoting drainage of residual water in the branch conduit.
U.S. Pat. No. 4,278,080 to Schuch is directed to a diving snorkel provided with a purge valve located in a branch conduit. This snorkel contains a large purge valve at the end of the branch conduit that connects with the snorkel tube at a place spaced substantially from the snorkel mouthpiece. The location of the purge valve prevents the premature venting of air that the water is effectively purged before any significant slippage occurs between the impelling air and the impelled water.
U.S. Pat. No. 5,868,129 to Christianson is directed to a snorkel having a conduit with an open end above the water surface and an underwater end which terminates in a collapsible chamber. A mouthpiece adjacent and above the chamber provides a flow path between the conduit and the interior of the diver's mouth. A check-valve in the opening between the conduit and the chamber allows water to flow between the conduit and the chamber but not in the reverse direction. The chamber also has a purge valve which allows water in the chamber to flow to ambient. Note that when hydrostatic pressure within the snorkel is greater than ambient, water will flow sequentially through the check-valve, chamber and purge valve to ambient.
U.S. Pat. No. 5,261,396 Faulconer et al is directed to a snorkel purge valve system incorporating an elongated chamber uniquely offset at an angle from the axis of the mouthpiece and having an introductory conduit for connection to an elongated tube of a snorkel. The elongated tube has an opening at one end of the inlet and outlet of breathing air. A mouthpiece is provided at the other end that is connected to the elongated tube by means of a fitting. The fitting can be in the form of a connection member incorporating the purge system. The mouthpiece contains grooves or flanges received on a mouthpiece mounting member for attachment. An outlet purge chamber is connected to the mouthpiece in an orientation such that it allows for drainage of water to flow there into, rather than the mouthpiece. The purge chamber has a purge valve distal from the mouthpiece and incorporates a chamber of significant volume for drainage from the mouthpiece and the elongated tube. The purge conduit has a plurality of ribs and grooves that are used to provide strength and can be used as a grip.
U.S. Pat. No. 4,928,710 to Campbell is directed to a mouthpiece for use with a snorkel with or without a purge valve. The snorkel includes a mouthpiece and contains a conduit in communication with an elongated breathing tube for the passage of air. The detachable snorkel mouthpiece incorporates a conduit having one or more interior grooves within the interior seating portion thereof. A tubular snorkel breathing extension having one or more exterior flanges engages the interior grooves which allows a firm fitting of the snorkel mouthpiece to the snorkel.
U.S. Pat. No. 5,117,817 to Lin discloses a snorkel having a tube within a tube configuration. The concentric tube configuration does not extend down to the mouthpiece and they are for intake and exhaust, respectively.
U.S. Pat. No. 6,302,102 to Giroux et al discloses a dry snorkel having dual side-by-side inner chambers leading to upper end check valves for inlet and exhaust, respectively.
U.S. Pat. No. 7,032,591 to Monnich discloses a snorkel having a walled lower purge area near the mouthpiece as shown best in FIG. 4.
U.S. Pat. No. 7,047,965 to Ball discloses a front-mounted snorkel having side-by-side tubes for inlet and exhaust leading to separate upper check valves.
Each of these prior art attempts has proven to be less than satisfactory for its intended purpose or too impractical to be built or not a commercially viable product. Therefore there is still a need for a practical solution which results in a snorkel having the ability to resist accumulation of water in the mouthpiece.